Summarizes the Bancorp's Recorded Investment in Impaired Loans and Related Allowance by Class (Parenthetical) (Detail) $ in Millions	3 Months Ended			9 Months Ended				12 Months Ended
	Sep. 30, 2015 USD ($) number		Sep. 30, 2014 number	Sep. 30, 2015 USD ($) number		Sep. 30, 2014 number		Dec. 31, 2014 USD ($) number
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	$ 2,202			$ 2,202				$ 2,457
Recorded Investment	1,916	[1]		1,916	[1]			2,233	[2]
Allowance	201			$ 201				295
Number of Contracts				11,227	[3],[4]	6,916	[5],[6]
Commercial Portfolio Segment | Commercial and Industrial Loans
Financing Receivable, Impaired [Line Items]
Allowance	64			$ 64				149
Number of Contracts				63	[3],[4]	83	[5],[6]
Commercial Portfolio Segment | Commercial Mortgage Loans, Owner-occupied
Financing Receivable, Impaired [Line Items]
Allowance	9	[7]		$ 9	[7]			14	[8]
Number of Contracts				14	[3],[4]	25	[5],[6]
Commercial Portfolio Segment | Commercial Mortgage Loans, Owner-occupied | Variable Interest Entity, Primary Beneficiary
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	28			$ 28				28
Recorded Investment	28			28				28
Allowance	$ 15			$ 15				$ 10
Number of Contracts | number	5		5	5		5		5
Commercial Portfolio Segment | Commercial Mortgage Loans, Nonowner-Occupied
Financing Receivable, Impaired [Line Items]
Allowance	$ 11			$ 11				$ 4
Number of Contracts				11	[3],[4]	19	[5],[6]
Commercial Portfolio Segment | Troubled Debt Restructuring On Accrual Status
Financing Receivable, Impaired [Line Items]
Recorded Investment	571			$ 571				869
Commercial Portfolio Segment | Troubled Debt Restructuring On Nonaccrual Status
Financing Receivable, Impaired [Line Items]
Recorded Investment	177			177				214
Residential Mortgage Loans
Financing Receivable, Impaired [Line Items]
Allowance	65			$ 65				65
Number of Contracts				855	[3],[4]	812	[5],[6]
Residential Mortgage Loans | Troubled Debt Restructuring On Accrual Status
Financing Receivable, Impaired [Line Items]
Recorded Investment	589			$ 589				485
Residential Mortgage Loans | Troubled Debt Restructuring On Nonaccrual Status
Financing Receivable, Impaired [Line Items]
Recorded Investment	24			24				33
Consumer Portfolio Segment | Troubled Debt Restructuring On Accrual Status
Financing Receivable, Impaired [Line Items]
Recorded Investment	384			384				420
Consumer Portfolio Segment | Troubled Debt Restructuring On Nonaccrual Status
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 52			$ 52				$ 63

[1] Includes $571, $589 and $384, respectively, of commercial, residential mortgage and consumer TDRs on accrual status and $177, $24 and $52, respectively, of commercial, residential mortgage and consumer TDRs on nonaccrual status at September 30, 2015.

[2] Includes $869, $485 and $420, respectively, of commercial, residential mortgage and consumer TDRs on accrual status and $214, $33 and $63, respectively, of commercial, residential mortgage and consumer TDRs on nonaccrual status at December 31, 2014.

[3] Excludes all loans and leases held for sale and loans acquired with deteriorated credit quality which were accounted for within a pool.

[4] Represents number of loans post-modification and excludes loans previously modified in a TDR.

[5] Excludes all loans and leases held for sale and loans acquired with deteriorated credit quality which were accounted for within a pool.

[6] Represents number of loans post-modification and excludes loans previously modified in a TDR.

[7] Excludes five restructured loans at September 30, 2015 associated with a consolidated VIE in which the Bancorp has no continuing credit risk due to the risk being assumed by a third party, with an unpaid principal balance of $28, a recorded investment of $28, and an allowance of $15.

[8] Excludes five restructured loans at December 31, 2014 associated with a consolidated VIE in which the Bancorp has no continuing credit risk due to the risk being assumed by a third party, with an unpaid principal balance of $28, a recorded investment of $28, and an allowance of $10.